TS is not wrong.
Technically a filter as we know it is also referred to as a lens because it
is a lens. For all intent and purpose, it serves the same function, so the terms 'filter' and 'lens' are interchangeable, and have been used in the photographic industry, even though the more technical term normally used is 'objective', and in most places, the majority refer to what you're talking about as a 'filter' although in some parts of Europe, to a much lesser extent, it's also referred to as a 'lens', usually with technical specs stated before, e.g., close-up lens, polarizing lens etc.
The use of a polarizing element in front of your camera lens, whether a wide angle or telephoto, serves the same purposes - to alter the polarization of light waves.
In more common photographic applications, this is done to either minimize or eliminate reflections off non-metallic surfaces, or in applications such as landscape photography, to darken or deepen blue skies.
There are other scientific and industrial applications of polarized light, although less common to ordinary folks like you and me.
And yes, further reading is recommended. Google 'Polarized light and filters in photography'.
If you really want to know what's going on:
http://www.physicsclassroom.com/class/light/U12l1e.cfm
Hope this helps.
